**Core Concept**
The fusion of a myeloma cell with an antigen-sensitized B cell lymphocyte is a process used to produce monoclonal antibodies in vitro. This technique, known as hybridoma technology, involves the fusion of two cells to create a single cell that can produce a large quantity of a specific antibody. The resulting hybrid cell, called a hybridoma, can be cultured in large quantities to produce large amounts of the desired antibody.

**Why the Correct Answer is Right**
The correct answer is a term used to describe the resulting hybrid cell that is formed by the fusion of a myeloma cell and an antigen-sensitized B cell lymphocyte. This process allows for the production of large quantities of a specific monoclonal antibody, which can be used for various medical and research applications. The fusion of these two cells is mediated by the use of a fusogen, such as polyethylene glycol (PEG), which disrupts the cell membranes and allows the cells to fuse.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not accurately describe the resulting hybrid cell formed by the fusion of a myeloma cell and an antigen-sensitized B cell lymphocyte.
**Option B:** This option is incorrect because it refers to a different process, where a B cell is activated by an antigen, but not fused with a myeloma cell.
**Option C:** This option is incorrect because it refers to a different type of cell fusion, where a somatic cell is fused with an embryonic cell.

**Clinical Pearl / High-Yield Fact**
Hybridoma technology has revolutionized the field of immunology and has led to the development of numerous monoclonal antibodies used in the treatment of various diseases, including cancer and autoimmune disorders. This technology has also enabled researchers to study the immune system in greater detail and has led to a better understanding of the mechanisms of immune responses.

**Correct Answer: C. Hybridoma.